Sometimes when the Ender Dragon spits her breath, it's for some reason invisible. So out of nowhere you get alot of damage and not knowing what it is. You can also just collect it using bottles like the normal Dragon's Breath. It's also not an exclusive glitch to the Windows 10 version. I beated the ender dragon with a friend on Android and he also had the same problem. Maybe it's a already a known glitch but I felt like I needed to report this since I beat the Ender Dragon very often in my world. And it's kinda the End of the game so I would say that should be glitchless.